Paradoxical and Retrograde Air Embolism from Pressurized Peripheral Bolus.

INTRODUCTION: Cerebral air embolism is a rare, yet serious neurological occurrence with unclear incidence and prevalence. Here, we present a case of fatal cerebral arterial and venous cerebral gas embolism in a patient with infective endocarditis and known large right-to-left shunt and severe tricuspid regurgitation following pressurized fluid bolus administration. Case Presentation. A 32-year-old female was admitted to the medical intensive care unit from a long-term acute care facility with acute on chronic respiratory failure. Her medical history was significant for intravenous heroin and cocaine abuse, methicillin-sensitive Staphylococcus aureus tricuspid valve infective endocarditis on vancomycin, patent foramen ovale, septic pulmonary embolism with cavitation, tracheostomy with chronic ventilator dependence, multifocal cerebral infarction, hepatitis C, nephrolithiasis, anxiety, and depression. After intravenous fluid administration, she became unresponsive with roving gaze, sluggish pupils, and hypotensive requiring vasopressors. CT of the brain showed diffuse arterial and venous cerebral air embolism secondary to accidental air administration from fluid bolus. Magnetic resonance imaging of the brain showed diffuse global anoxic injury and flattening of the globe at the optic nerve insertion. Given poor prognosis, her family chose comfort measures and she died. CONCLUSIONS: Fatal cerebral air embolism can occur through peripheral intravenous routes when the lines are inadequately primed and fluids administered with pressure. Caution must be exercised in patients with right-to-left shunting as air may gain access to systemic circulation.

COVID-19 Related Acute Hemorrhagic Necrotizing Encephalitis: A Report of Two Cases and Literature Review.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus, has proven neurotropism and causes a multitude of neurologic manifestations. Acute hemorrhagic necrotizing encephalitis (AHNE), though rare, can be seen in patients with severe infection and is associated with devastating neurologic outcomes. The true prevalence of this syndrome is unknown due to underrecognition, difficulty in timely acquisition of neuroimaging, and high mortality in this subset of patients escaping detection. It is a distinct clinicoradiological syndrome, with patients suffering from rapidly worsening encephalopathy and coma within the first two weeks of severe illness and hemorrhagic necrotizing parenchymal changes on neuroimaging. The pathophysiology of this syndrome is unclear but hypothesized to occur due to cytokine storm, blood-brain-barrier dysfunction, and direct viral-mediated endotheliopathy. Diagnosis requires a high index of suspicion in patients who have unexplained persistent severe encephalopathy associated with COVID-19 infection. Most patients have elevated systemic inflammatory markers and severe lung disease with hypoxic respiratory failure requiring mechanical ventilation. MRI is the imaging modality of choice, with a distinct neuroimaging pattern. CSF (cerebrospinal fluid) studies have a low yield for viral particle detection with currently available testing. While long-term outcomes are unclear, early immunomodulatory treatment with intravenous immunoglobulin, plasma exchange, and steroids may portend a favorable outcome. We discuss two cases of COVID-19 related AHNE and also include a pertinent literature search of similar cases in PubMed to consolidate the AHNE clinical syndrome, neuroimaging characteristics, management strategies, and reported short-term prognosis.

Fatal Brain Injury Following Carbon Dioxide Angiography.

INTRODUCTION: Carbon dioxide (CO2) as a contrast agent has been in use as early as the 1920s for visualization of retroperitoneal structures. Digital subtraction angiography (DSA) using CO2 as a contrast agent for vascular imaging was developed in the 1980s. Currently, CO2  angiography is an alternative agent in patients with chronic kidney disease (CKD) and those who are at risk of developing contrast-induced nephropathy. However, CO2 causes neurotoxicity if the gas inadvertently enters the cerebrovascular circulation leading to fatal brain injury. CASE PRESENTATION: A 71-year-old female with h/o sickle cell trait, hypertension, obesity, metastatic renal cell cancer status post nephrectomy, bone metastasis, chronic kidney disease was admitted for elective embolization of the humerus bone metastasis. Given the high probability of contrast-induced nephropathy, CO2 angiography was chosen for embolization of the metastasis. During the procedure, the patient became unresponsive. Emergent medical management with hyperventilation, 100% fraction oxygen inhalation was performed. Her neuroimaging showed global cerebral edema. An intracranial pressure monitor was placed which confirmed intracranial hypertension. Hyperosmolar therapy was administered with no improvement in clinical examination. She progressed to brain stem herniation. Given poor prognosis, the family opted for comfort measures and the patient expired. DISCUSSION AND CONCLUSIONS: Inadvertent carbon dioxide entry into cerebrovascular circulation during angiography can cause fatal brain injury. Caution must be exercised while performing CO2  angiography in blood vessels above the diaphragm.

Developmental Venous Anomaly Presenting with Spontaneous Intracerebral Hemorrhage, Acute Ischemic Stroke, and Seizure.

Developmental venous anomaly (DVA) is the most common, benign, congenital vascular malformation of the brain and mostly an incidental finding on imaging. The exact etiology of DVA is unknown but thought to be due to medullary vein thrombosis during embryonic venous development. DVA is generally asymptomatic although associated neurologic deficits and seizures have been described. Several reports of DVA causing neurovascular compression, obstructive hydrocephalus, venous infarction, and intracerebral hemorrhage (ICH) have been described. In this report, we discuss a patient with fluctuating neurological symptoms found to have multiple DVA, predominantly draining into the deep venous system. To the best of our knowledge, DVAs leading to simultaneous ischemic stroke, intracerebral hemorrhage, and seizures are not reported in the literature. We reviewed the relevant literature and discussed the epidemiology and clinical and radiological characteristics of DVA.

Decompression Hemicraniectomy for Refractory Intracranial Hypertension in Reversible Cerebral Vasoconstriction Syndrome.

Reversible cerebral vasoconstriction syndrome (RCVS) is a disorder of dysregulation of cerebrovascular tone resulting in transient segmental vasoconstriction which resolves in 1-3 months. Cerebral edema is an underrecognized complication in RCVS. It is likely multifactorial. This edema can lead to intracranial hypertension that can be refractory to medical management. Limited evidence exists regarding surgical management of intracranial hypertension in RCVS. We present a 29-year-old Caucasian right-handed female patient with a medical history of migraine, polysubstance abuse presented to the emergency department (ED) daily for 3 days with the chief complaint of recurrent thunderclap headache. She declined neuroimaging and lumbar puncture. She was treated for migraine with abortive medications with no improvement. During the third ED visit, she became lethargic with right-sided homonymous hemianopia. Computerized tomography of the brain showed left parietal intracerebral hemorrhage with intraventricular extension, cortical subarachnoid hemorrhage, and diffuse cerebral edema. Digital subtraction angiography showed multifocal moderate-to-severe segmental vasoconstriction suggestive of vasculopathy. Oral verapamil was initiated. Continuous intracranial pressure monitoring showed uncontrolled intracranial hypertension, despite maximal medical management with hyperosmolar therapy, induced coma, and hypothermia. Decompressive hemicraniectomy with duraplasty was performed for refractory intracranial hypertension. We provisionally diagnosed her with RCVS. She was discharged to inpatient rehabilitation with residual right homonymous hemianopia. Transcranial Doppler study during follow-up showed improved mean flow velocities. She continued to have residual cognitive deficits with complete resolution of headache.

Intracranial Calcification Masquerading as Hemorrhage in a Patient with Multiple Myeloma Presenting with Facial Neuropathy.

Multiple myeloma is an immunoglobulin-producing plasma cell neoplasm that commonly affects the bones, kidneys, the hematopoietic system, and rarely the nervous system. Peripheral nervous system involvement in the form of cranial neuropathy, radiculopathy, and polyneuropathy are common. Compressive myelopathy constitutes the majority of central nervous system disorders followed by cerebrovascular disorders, intracranial plasmacytomas, and leptomeningeal myelomatosis. Cerebrovascular complications such as acute ischemic stroke and transient ischemic attack are not uncommon. Intracerebral hemorrhage, although infrequent, can be secondary to refractory hypertension from renal failure and intratumoral hemorrhage in intracerebral plasmacytomas. Metastatic calcifications in lungs, liver, and skin with high levels of serum calcium and phosphate are seen in patients with multiple myeloma, but intracerebral calcifications are not common. We report an unusual case of intracranial calcification masquerading as acute intracerebral hemorrhage in a patient presenting with acute facial weakness.

Cocaine Induced Bilateral Posterior Inferior Cerebellar Artery and Hippocampal Infarction.

Cocaine is one of the most commonly abused recreational drugs, second only to marijuana. It blocks the reuptake of neurotransmitters such as norepinephrine and dopamine, that leads to persistent post-synaptic stimulation responsible for its excitatory effects. Cocaine-related strokes, both ischemic and hemorrhagic, have been well described in the literature and cerebral vasospasm is hypothesized as one of the major mechanisms responsible for the presentation. Although cases of posterior circulation infarction were previously reported, we herein report a rare presentation of a cocaine-induced bilateral posterior inferior cerebellar artery and hippocampal infarction in a middle-aged female.

Wernekink commissure syndrome with palatal myoclonus at onset: a case report and review of the literature.

BACKGROUND: Wernekink commissure syndrome causes a peculiar combination of internuclear ophthalmoplegia, dysarthria, and delayed-onset palatal myoclonus. Palatal myoclonus is thought to be secondary to delayed hypertrophic degeneration of the bilateral inferior olivary nuclei secondary to involvement of bilateral dentatoolivary tract. We describe a case of a patient with early-onset palatal myoclonus. CASE PRESENTATION: A 53-year-old Caucasian man with several vascular risk factors presented to our emergency room with slurred speech, double vision, difficulty with swallowing and walking, and rhythmic contractions of the soft palate. Brain magnetic resonance imaging showed an acute infarct of the right caudal midbrain and an old infarct of the right medulla. We hypothesize that the cause of early palatal myoclonus in our patient was a two-hit mechanism with degeneration of the right olivary nucleus resulting from prior right medullary lacunar stroke with the new infarct affecting the dentato-rubro-olivary tract on the left side, causing bilateral dysfunction initiating palatal myoclonus. CONCLUSIONS: Wernekink commissure syndrome with palatal myoclonus at onset suggests the presence of a prior ischemic insult in the medulla. Careful examination is important to identification of this presentation.

A Case Report of Recurrent Takotsubo Cardiomyopathy in a Patient during Myasthenia Crisis.

INTRODUCTION: Patients with myasthenia crisis can develop Takotsubo stress cardiomyopathy (SC) due to emotional or physical stress and high level of circulating catecholamines. We report a patient who developed recurrent Takotsubo cardiomyopathy during myasthenia crisis. Coexisting autoimmune disorders known to precipitate stress cardiomyopathy like Grave's disease need to be evaluated. CASE REPORT: A 69-year-old female with seropositive myasthenia gravis (MG), Grave's disease, and coronary artery disease on monthly infusion of intravenous immunoglobulin (IVIG), prednisone, pyridostigmine, and methimazole presented with shortness of breath and chest pain. Electrocardiogram (ECG) showed ST elevation in anterolateral leads with troponemia. Coronary angiogram was unremarkable for occlusive coronary disease with left ventriculogram showing reduced wall motion with apical and mid left ventricle (LV) hypokinesis suggestive of Takotsubo stress cardiomyopathy. Her symptoms were attributed to MG crisis. Her symptoms, ECG, and echocardiographic findings resolved after five cycles of plasma exchange (PLEX). She had another similar episode one year later during myasthenia crisis with subsequent resolution in 10 days after PLEX. CONCLUSION: Takotsubo cardiomyopathy can be one of the manifestations of myasthenia crisis with or without coexisting Grave's disease. These patients might benefit from meticulous fluid status and cardiac monitoring while administering rescue treatments like IVIG and PLEX.

White Matter Changes in Corpus Callosum in a Patient with Idiopathic Normal Pressure Hydrocephalus.

Idiopathic normal pressure hydrocephalus (INPH) is characterized by the clinical triad of gait and cognitive dysfunction and urinary incontinence. Ventriculoperitoneal (VP) shunting is often required for treatment. Review of literature shows few case reports discussing benign magnetic resonance imaging (MRI) T2 hyperintense changes in the corpus callosum of NPH patients after shunting due to mechanical compression of the middle and posterior regions of the body against falx cerebri leading to ischemic demyelination. These changes can be a delayed phenomenon and may interfere with clinical evaluation and may lead to unnecessary procedures and investigations. We present a patient with NPH who was admitted to the neurocritical care unit in coma with quetiapine and trazodone overdose. Diffuse changes in the body of the corpus callosum were seen on MRI suspicious for acute vasogenic edema due to drug overdose. However, it was later determined to be due to the VP shunting for the NPH. We report this case to raise the awareness of neuroimaging changes in patients with NPH who have VP shunting.

Brugada syndrome in a patient with amyotrophic lateral sclerosis: a case report.

BACKGROUND: Amyotrophic lateral sclerosis is a fatal neuromuscular disorder characterized by progressive death of the upper and lower motor neurons in the central nervous system. Patients with this disease die mostly as a result of respiratory failure; however, owing to prolonged survival through assisted ventilation, cardiovascular causes are increasingly responsible for mortality. We report what is to the best of our knowledge the first case of type 2 Brugada syndrome causing ventricular tachyarrhythmia and cardiac arrest in a patient with upper limb onset amyotrophic lateral sclerosis. CASE PRESENTATION: A 48-year-old Caucasian woman with a significant past medical history of papillary thyroid carcinoma status postresection, pulmonary embolism on anticoagulation, and a recent diagnosis of right upper limb-onset amyotrophic lateral sclerosis presented to the emergency department of our hospital with acute on chronic shortness of breath. On further evaluation, she was found to have hypoxic and hypercapnic respiratory failure and was placed on bilevel positive airway pressure ventilation. Her 12-lead electrocardiogram showed sinus rhythm with J-point elevation, saddle-shaped ST segment elevation, predominantly in V1 and V2 with no significant QTc prolongation. No troponin elevation was noted in her laboratory workup. Because she was unable to protect her airway, a decision was made to intubate her. After 1 minute of induction with etomidate and succinylcholine, she went into pulseless ventricular tachycardia and fibrillation requiring three cycles of cardiopulmonary resuscitation with high-quality chest compressions, three doses of epinephrine, and a loading dose of amiodarone prior to return of spontaneous circulation. She was further evaluated by cardiology services and was diagnosed with type 2 Brugada syndrome, for which she was started on quinidine. Her respiratory failure and the drugs she received for intubation likely caused her ventricular tachycardia to occur in conjunction with an underlying Brugada pattern seen on an electrocardiogram. The results of evaluation of her genetic panel for Brugada syndrome were negative. She was subsequently discharged to home in stable condition after a 10-day hospital stay. CONCLUSIONS: Amyotrophic lateral sclerosis is a progressive neuromuscular disorder with significant mortality. Respiratory failure is the leading cause of death, but lately, owing to increased survival associated with early tracheostomy and positive pressure ventilation, there has been an increasing trend in the identification of cardiovascular causes of mortality, especially arrhythmias, that may need periodic electrocardiographic surveillance.